Spam coming from Africa could be about to boom thanks to new broadband infrastructure in the Eastern half of the continent, according to Symantec’s MessageLabs division.

The proportion of global spam sent by Africa is still a tiny 3 percent, by MessageLab’s reckoning, but that is up from the 2 percent in April 2009. At a time when global spam levels are stable, the extra 1.2 billion spam emails is large enough to count as a new trend.

Although the Western side of Africa, and North-Africa in particular, still account for the overwhelming volume of African spam, the company notes the lighting of a new undersea fibre cable running down the eastern edge of the continent in July 2009 was probably the key development.

Coming ashore in Djibouti, Kenya, Tanzania, Madagascar and Mozambique, the 8,400Km long, 1.2 terabit link could explain why that side of continent has seen its share of the African spam phenomenon rise.

“The new undersea fiber optic cable along the east coast of Africa has enabled rapid growth in the number of users obtaining high speed connections to the internet creating a great opportunity for attackers to infect new machines and create new bots,” said MessageLab’s analyst, Paul Wood.

A growing number of users in countries served by the cable had access to broadband links but without awareness about the need for computer protection, opening a new front for botnets, he said.